I had a dog who did this and it was amazing. It may be because dogs are warmer-blooded than humans or cats (I read where dogs' normal body temperature is around 102F). So they just dont' get cold as easily. Also they don't sweat: they lose heat by panting, so cold water simply doesn't cool their skin like it does ours.

My cat's normal temperature is also that high, so that argument doesn't hold water;) As a former dog-owner I think it's because dogs have a more developed sense of fun compared to cats and humans, not that they're stupid.

It is as a result of their instinct, developed through the animals history and evolution.

Some large cats such as tigers need to swim often in their natural habitat, but most do not need to swim to survive.For dogs however, as wolves and wild dogs, swimming would have been more common.

It is always possible for them to override their instinct, with knowledge from their life experiences. I know a dog that is frightened of water after he was thrown in once, and I have seen a cat on You Tube that likes showers because it wanted to copy its owners.

I think that it probably depends on the type of dog. We have a golden retriever. A golden is a water dog, he has webbed feet and fur with a thick under layer that is dense enough to be waterproof. Retrievers have been well adapted to swimming and enjoy it, the water proof layer of fur stops them getting very cold from the water. There is no reason why Sam should not jump into a cold pond to chase ducks, and so he does.

Because the dog has to loose heat by panting - and I think they are generally warmer then humans and cats - They can't cool down as quickly and effectively. The cats don't like jumping into ponds as their hair traps the water and they can't get it off. Dogs like jumping in because of exactly that - they get cool moisture trapped in their fur and stay cool for longer!

well, not that this is a scientific explanation, but just from observation: my dog jumped into pools and lay down in puddles only when it was really hot. If the outside temperature was cold, he'd hesitate - or go in and VERY quickly go back out again.

He usually runs round like a loony, then goes and uses a puddle or a pool to cool off. When he comes out he never shakes the water off, but just let it drip off (unless it's cold outside), presumably because once he shakes it off, a lot of the cooling effect has gone.

the other comparisons between cats and dogs don't hold. Cat's and dogs both don't sweat, so when a cat is really hot, it too will pant. and both their body temperature is 101.5F.

So in the end it's all down to Genes. Dogs are like kids, and kids too like jumping into puddles and would quite easily jump into a pool of deeper water, if adults didn't stop them. It's playful behaviour. the running round helps them keep their temperature up.

Cats, are more like adults. They see water and they think: urh, cold. They don't mindlessly run around just for the fun of it (they have a purpose in everything they do), so don't build up unnecessary heat.

The domestic cats we keep today originally came from hot, dry countries; any cat owner can attest to their love of warmth! They hate getting cold, and I suspect their general dislike of water has something to do with their desert origins.

Dogs have been bred from wolves and in the process, humans have selected the puppy-like traits that persist into adulthood. Hence the playfulness and jumping into water.

Cats on the other hand have retained a fierce independent streak and their breeding has focused on still being able to hunt independently. No kitten-like traits there. Even kittens sometimes aren't that friendly. And dogs are more social to begin with. So cats still have more 'wild' traits whereas dogs are more playful, social, child-like and dependent on humans.

It's hard to generalize on this behaviour, even across one breed. We have two Soft Coated Wheaten Terriers of a similar age, and most days, they both go down to the beach for a walk. One, the bitch, immediately heads for sea and always goes out far enough so she can have a swim, even in the depth of winter. Her companion however, rarely ventures further in than his paws, and lets her know he doesn't approve.

Funnily enough, if you try to use a hose pipe to clean the sand off the female before she is allowed inside, she struggles and complains like you're tring to dose her with acid - even though the temperature is usually higher than the sea she has just been in.

I suspect adrenalin has a lot to do with it - just like humans, awareness of pain or discomfort is dulled when excited or in the 'flight or fright' mode.

It's a matter of size. Think of each cell in your body as a little heat engine. The rate at which you lose or gain heat from your environment depends on your surface area to volume ratio. Surface area increases on the square of length. Volume increases on the cube. Doubling, say, the body's length quadruples the surface area (e.g. skin) but makes weight (the number of cells) go up by a factor or eight.

An eighty pound dog who jumps in the water has four times the area from which to lose heat as a ten pound cat. Bowser loses heat from the cold only half as fast as Ginger. That's why your dog has a better time in the water than your cat.

A 160 pound human would have an even easier time except for two things, fur and breeding. As every hiker knows, wool keeps you warm even when it's wet. Dogs and cats are covered with fur. We are not. Wet fur doesn't keep warm air trapped between its fibers, but it does provide a certain amount of insulation.

One indication that it's size that makes Kitty unhappy to be in the pond is to take a look at Kitty's larger relatives. The big cats, lions, tigers, leopards, jaguars et al are perfectly happy in the water. They enjoy swimming. A friend who worked with then at a big cat center in the States said that the problem was getting them out of the water some days.

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